The invention relates to a multiple chamber sequential inflation seat cushion. More particularly, the invention relates to a seat cushion having multiple inflatable chambers, which are selectively inflated and deflated sequentially in a predetermined order.
Even the most comfortable chair can become uncomfortable if one sits in it long enough. The pressure of the chair upon the buttocks and upper thighs has a tendency to cut-off circulation and cause discomfort.
When most people become uncomfortable from sitting too long, they will stand up, and allow the blood to circulate in their upper thighs and buttocks. Many people, such as those suffering from disabilities, do not have the ability to get out of their chair. In particular, people bound to wheelchairs and the like are forced to deal with the daily discomfort caused by prolonged sitting.
Several devices have been proposed which seek to deal with the discomfort associated with prolonged sitting by providing inflatable areas within the seat. U.S. Pat. No. 4,840,425 to Noble discloses an automotive seat which contains a plurality of inflation chambers which are sequentially inflated from the front of the seat toward the back. U.S. Pat. No. 5,379,471 to Holdredge discloses a pneumatic wheelchair cushion which has a plurality of air sacks which are sequentially deflated for a preferred period of twelve seconds per minute by a rotating air distributor.
While these units may be suitable for the particular purpose employed, or for general use, they would not be as suitable for the purposes of the present invention as disclosed hereafter.